Air-brake testing apparatus



Feb. 6, 1940. R, SIMPSON f 2,189,184

AIR -BRAKE TESTING APPARATUS Filed Malfch 19, 1938 3 Sheets-Sheet 1Im/ENTOR. /fw )Aya/w BY @f4/Mm A TTORNEYS.

Feb. 6, 1940. R slMPSON i 2,189,184

AIAR -BRAKE TESTING APPARATUS Filed March 19, 1958 5 Sheets-Sheet 2 Feb.6, 1940. R. SIMPSON 2,189,184

AIR-BRAKE TESTING APPARATUS Filed March 19, 1938 3 Sheets-Sheet 3 IN VENTOR. /M' JW BY ff/M7 @MU/@22% A TTORNEYS.

l j Auitliep'srmrgs,

Patented Feb. je, 194e IRQBRAKE r1.7ns'151uerAeinenAtrusv` y n NRobertSimpson, Newell, Pan",` 4 n l, App1ieation-Marhi',193s,serialN0.19s,943.

My invention `relates tothe `testing yof .fluid-v aidofja pressure gaugein the testingapparatus` and a Watch-the rate of` air leakageinrthebrake system oithe train" is" checked.` If` the .leakage isfwithin permissive tolerance, the inspector operated zbrakes,particularly `air brakes, and more particularly the `air brakes ofrailroad trains. Theinvention consists in improvements in apparatus,by'fvirtue-of which theltests may befmade more readily and quickly. vThe invention will be `describedas practised in testing the'ar'brakes ofrailroad trains..

As `those familiar vvithfthe` art know, each railroad carisequipped withbrake apparatus lwhich is .adapted to be .operated Icy-air underpressure.

lmgfeneral, such lbrake `apparatus includes an V auxiliary reservoirforcompr'essed air, two .pneu- Amatic'plungers triple valves, retainingvalves,

vand la brake-pipe, all lorganized and interconnected in known way to`operate-.the brakes of the car. Insert/ice, the brake-pipes of lthecars t of ajtrain are interconnected, by means of flexiil ,therear endof the train the train-pipe is closed.

ble `coupling hoses, and (provide `a continuous air passage, knownv asthe-train-pipe, that extends from one, endI of the trainto the other.`.At `the head .end ofthe :train this train-pipe communi-l cates'through Vth ,"usual` engineers brake valve The" main reservoir,lconstantly .supplied` with air by a compressor inthe engine, chargesythe,train-pipe and -auxiliaryfreservoirs and valves `of fthe `several carswith air at Anormal operating pressure-seventy pounds, pressure in the lcase of freight ytrains and one hundred andten pounds in the casesofpassenger trains, and when the v'train-,pipe `is charged with air atsuon y.pressure,l the brakes; of `all the cars stand. in releasepositionsf When the ,pressure in thev train-'pipe is reduced, `the brake`apparatus ofthe several cars operate `to apply all fbrakes of the*train.

f The brakes fare, held .in `applied positions until the air pressure`in the 'train-pipeisrestored to normal valuaor `substantially so.'I-his control of the pressuregwithin Lthe train-pipeis veffected in:known way throughmanipulation of the en- `@,'ineens brake valve.`

`Whena train Ais made up in a terminal,` and vsonietimes when aftrainouton the road is at vrestin a station, .it is required that the Abrakesoffeach car shall be testedandinspected. In

making such test Ythe 'trainfpipe is connected 4 .through a testingapparatus arranged at one -end of the trainer carsto a supply ofcompressed and the auxiliary reservoirs andthe train- ,pipe of the kc:oupled cars are Ycharged with air `'unt-il .normal operating `pressureis established. K

Then communication V.betweeny the air supply f a and the .train-.pipeis, interrupted, `ands-With the vents air from the testing apparatus`until the .pressure in the ',-trainpipe is reduced i twentypounds,'.with the consequence that afservloe applicatio-n-oi theAbrakesis' effected. `While the brakes are thus set, the` inspector goesthe length ofthe train, observingeachvbrake to seethat `it `has operatedproperly. "Then hereturns, to the testing apparatus at lthe head -end ofthestrain` and re-establislies communication between Lthe supplyofcompressed air andthe train-pipaand recharges theI train-pipe tonormal operating pressure. i This releases thepbrakes; Againltheinspector walksv the length of the train,` looking atieachbrake to makesurethatitisin proper release position. `Upon completing the test, the

inspector returns -to the head end of thetrain;` v disconnectsthetesting apparatus, and makes his report. Thus itwill be .understood thatinglrnak-` y. the ftestthe inspector must travel `the length ofrthetrain .four times. "The time consumed and Y the cost are great', evenWhen` tvvo inspectors work together on the rjob, and the 1problem isbecoming more acute with the @growing prac-1 vtice ofoperatingfreightrtrains of a `mile orfniore i in length. 3 l,

My invention consists in refinements `in :test` ing apparatus, by virtueoffwhich itis `necessary vide meansin the testing apparatusiorrecharging the trainspipe and releasing 'the brakes, while theinspector, having gonethelength of the train and inspected` the brakes`in `applied vent the train-pipe and then close it again. .The `testingapparatus at the head end of the train 'operates to recharge thetrain-pipe injthe manner mentioned.

`In the accompanying drawings testing ap',-

'paratus embodying the invention is illustrated.

Fig. 1 is a view in side elevation ofarelatively simple form of theapparatus, with the means lfor the inspector to gowthe `length `ofthetrain only once andV return. More particularly, flpropositions, stillat the remote end of the train. C

for supplying compressed "air, and..a.train of cars, illustrateddiagrammatically and )to-smevtllff` eriscale; Fig. II is a fragmentaryview-showing .partly in side..elevation and partly. in vertical.

section a portion of the apparatus to larger scale, and illustrating amodification in detail; Fig.`III

`is a view in side elevation oi a more refined form of testing apparatusin which the invention has been embodied; and Fig. vIV is a fragmentary"the invention embodying still other kmodifica- I tions.

, fromI the air reservoir to the train-pipe.

Referring to the drawings, the brake-testing apparatus shown in Fig. Iincludes ina tubularbody B, constructed in this case` of standardpipefittings, and provided at its'opposite ends with hose couplings 3 and d,by means. of which the apparatus may be connected in usual way in a lineL of flow from a reservoir R of compressed air tothe train-pipe TPv of atrain of cars 'I' whose brakes are to be inspected'and tested. vAn

vair compressor C maintains the supply of lcompressed air irl-reservoirR at a pressure in excess ofthe normal train-pipe pressure ('70 poundsor 110. pounds, as already mentioned), `and it will be'l understood thatthe reservoir and compressor may be they main reservoir and compressorof the locomotive which'jis to pull the train. Alternately, thereservoir: and compressor may, as

, here 's ljiown, consist in a permanent piece of apparatus'in therailroad yard in which trains are inade` upland inspected. Y

llIn accordanceI with the invention, the testing apparatus -includes atwo-branched line of ow One branch of such line of' flow is provided inthe tubular body portion to which the reference letter B is immediatelyapplied, and in this branch two pressure gauges I, I and a manuallyoperated valve'2 are provided, with a flow-constricting cone (or anorifice plate) included between the gauges, to 'prevent undue yviolenceof flow when the valve 2 is opened and' air is charged from thereservoir --R into the train-pipe TP. The

second branch of such line of now is provided in pipe sections 5, 1, andS, connected together in the form of an inverted U, and assembled in theapparatus in such manner that the gauges I, I andthe valve 2 lie betweenthe legs of the U. A n auxiliary valve 9 is included in this secondbranch, and it will be perceived that by opening such valve,communication may be established between the 'air reservoir R and thetrain-pipe TP, whether or'not the valve 2 is open or closed.

-Th'e invention consists in instrumentalities that are responsive to thecontrol of the inspector, when he is at the remote end of the train, foropening the' auxiliary valve S.

Such instrumentalities include yielding means thattend to turnthe valvegfrom closed to open position, and means for normally holding the valve,against the urging of said yielding means, in closed positionv until theair pressure in the trainepipe is intentionally reduced to a value belowthat which effects a service application oi the brakes being inspected.In the apparatus of Fig.' I, suohyielding means consist in a spring III,

tending to swing the operating handle I I of the l valve 9counterclockwise from the horizontal position illustrated, in which thevalve is closed,

1nto a vertical position, in which the valve isopen;

and the'means for holding the valve in closed p osition consist in atrip-arm I3 which is: pivoted at its'lowerY end to a rigid bar I2 thatspans the pipes' and 3. f'Ihe upper, distal end of the trip-- arm lisadaptedto engage the outer end of the handle IIl from beneath and holdthe valve against the tension of spring I in closed position. A plungerrod I5 in a cylinder I6 is movable in response to an intentionalreduction in pressure in the train-pipe, to swing the trip-arm fromengagement .with the handle II and permit the spring ID to open thevalve.A Further detail in the structure and operation of the apparatuswill be considered in the ensuing description of a brake inspection. i

' Preparatory to 'making lan inspection, .the upper hooked end of thespring Inis disengaged from the pin 3| that secures it to the operatinghandle II of valve 9, and both valve 9 and valve 2 are closed. Thetesting apparatus is then connected in line L between the reservoir Rand the train-pipe TP. When this has been done, the 'valve 2 is openedand air is fed from the reservoir R into the train-pipe, until thegauges I, I indicate that the pressure in the train-pipe and brakesystem of the train has reached normal operating value, 70 pounds in thecase of the-illustrated freight train. Such charging of the systemoperates to release the brakes. of the train.

The pressure existing inthe train-pipe and line L is eiective throughbranch pipe 3 and pipe fittings I'I upon the left-hand face of a pistonI8 (Fig. 1I) which is secured within cylinder I6 to the end of plungerrod I5. Between the piston and the head I9 of the cylinder a compressiony springiopposes movement of the piston and rod under" the influence ofsuch 'air pressure. While air is being initially charged into thesystem, the rising pressure gradually shifts the inder head I9, andarrests the movement of the piston; in such positionof the piston thespring is fully energized. As already mentioned, the charging oi' thesytem is continued until the pressure reaches the' value of 70 'poundsand the valve 2 hasbeenclosed. The plunger rod I5, pros jecting fromcylinder. I6, 'extends with sliding fit through the'trip-arm I3, and atits outer end carries a block-2|. When the partshave come to rest,under'the conditions described, the trip arm I3 is' set bene'aththe`valve handle II, and the spring IB is expanded and its free end hookedupon the pin 3| on the handle. The positions of the parts at this stageof the operation are shown in Fig. I,'it being noted that the block- 2Ilies at an interval tothe right of the triparm. All is in readiness toproceed with the test. The inspector opens a normally closed angle-cock22 and releases air from the charged system, until the gauges show a 15pound drop in pressure; that is, until the pressure in the train-pipe isreduced to 55 pounds in this case. The anglecock is then closed and thegauges are watched for one minute, to note the pressure loss in thesystem. If the loss exceeds seven pounds in such interval of time, theinspector cannot approve the train for road service, but must nd thesource, or sources, of leakage and make necessary repairs. If the lossis less than this critical limit, a limit xed by law, the inspector goesforward with the test. (It may bev remarked that some railroads havevoluntarily set lve pounds per minute` as the limit of leakage whichwill be permitted.)

The angle-cock 22 is again'opened andthe pressure is permitted -to fall-to a value of 50 pounds, at which pressure the brake apparatus of theseveral cars of the train operate to eiect fully compressed. This fallinpressure in the' train-pipe relieves the pneumatic pressure onthepiston i8 in the testing apparatus at the head end of the train, withthe consequence and eiliect that the spring 2t expands and shifts thepistonl i8 and rod i5 to the left'. The block 2| on the shift ing rod l5moves. into contact with the sideof y the trip-arm i3, and swingssucharm in'counterclockwise` direction. The distal end of the triparm isthus disengagedirorn the valve-operating handle Il (cf. broken-lineposition" in Fig. II) l,

and the handle, under the stress of spring ll,

swings downward and opens the valve 9. Thereupon, branch line l, l, ilof iiow opened and communication is established between the supply R ofcompressed air and the train'pipe, and the train-pipeis recharged to thepressure of the air supply, which is equal to, or in excess of, the'pressure (70 pounds) necessary to effect Vthe release of the brakes.When the Vbrakes of the train have thus been released, the inspectorreturns along the lengthof the train and checks each brake, making noteof any that have not operated properly. Upon reaching the head end ofthe train, with the inspection completed, the testing appa' ratus isdisconnected andthe customary report made to the yardmaster or othersupervisor.`

,'I'hus, it will be perceived that my apparatus makes for substantialsavings in time and labor; it eliminates the` need of two men to do theVjob, and does not require signaling betweenthe head end and rear of thetrain.

It may be remarked that, if the train being inspected is a long train,ythere is a possibility that the leakage of pressure from the system`may, while the` attendantis making his Ainspection with the brakesapplied, cause the pressure inthe train-pipe to fall 'below "thel'brake-applying pressure of 50 pounds, in such manner that the trip-armi3 ywill be thrown and the valve 9 opened before the end of the train isreached. In order to prevent such an occurrence; the main valveV 2 maybe allowed to stand in slightly open position, to permit the reservoirto supply air to the system in quantity equal `to `thatlost by leakage.

Another feature of .adjustment fis to be noted.r

The block 2l is'adjustable axially of the piston l yrod 15,150 the endthat the valve-releasing move ment ofthe trip-arm may be accuratelyresponsive to desired` critical value of pressure relief in thetrain-pipe. Conveniently, the rod and the block `are threaded, wherebythe block may be rotated to effect such adjustment.

'I'he spring ld andr the plunger l5 are err-fy emplary only ci the meansfor achieving the ends in view. In modification,y the operating handleof the valve 9 may be counter-weighted, asshown at lbin Fig. IL'andneedless to say the designer may operate to opcnthe valve."

Thus, the pressure in the train-pipe may be maintained at brale-applyingvalue, untilv handle,A so that the counter-weight` (or spring) In `I"igs.-III and IV, a refined andlrrnorecom# pact "embodiment of theinvention is illustrated.

AIn this rened structure, as in the-structure first described, couplings3a `and la are provided for connecting vthe apparatus in the line offlow between the air reservoir and the train-pipe. Be-

tween the couplings 3a and 4a, the line of flow through the apparatusincludes two branches, one branch through the bodyof a valve 9a, and theother through interconnected pipe `sections 6a, la, and lla.` Theapparatusincludes a gauge la arranged to indicate pressure in the lineof flow, on each side of the valve 9a. It will be understood that, savefor `the connections 6a, la, 8a and certain additional 4parts presentlyto be described, the structure illustrated in Figs.

III and IV is a piece of apparatus well known to the art. l

A manually operated valve 2a controls llow in` one branch of the doubleline of flow, and valve Se. controls iiow in the other. Theyoperatinghandle Ha of the Valve 9a is provided with a lug Hb, and the distal endof a pivotally supported trip-arm i3d, which is backed by a leafmayprovide other known sorts ofmotorsto eiieot the desired release ofthezvalve-operating,

spring leb, is adapted to engage the lug I l b and Y lock the handleila, against the'tensionof a spring Sila, with the valve in closedposition. Within a vertical cylinder I 6a, a compression spring 2daexerts a thrust upon the upper face of a piston 53a, tending to shiftthe piston downward; a plunger rod 15a, securedto the piston kandprojecting from the upper end of the cylinsur der, `extends with slidingt through the triparm i3d, and above such trip-arm carries a block 25a;thelower end of the cylinder lGacommunicates with the line `of flow onthe trainpipe side (theright-hand side) of the valve 2a, and air attrain-pipe pressure, acting on the bottom of the piston i3d, opposes thethrust of the spring above. v

Theprocedurein making a test is the same as that already described, andit remains only to say that a relief valve 22a. (or other suitablemeans) is provided on the train-pipe side of the valve 2a, so that inthe initial stages of the test the charged system may be vented to the`open atmosphere, to reduce the train-pipe pressure from brake-releasingto` brake-applying value. When the inspector has gone the length of thetrain withl the brakes applied, he momentarily vents the train-pipe,with the consequence and eilect that the spring 25a expands, the plungerrod |5a descends, the trip-arm` 63a swings downward, the handle llarotates under the stress of spring Staand opens valve 9a, and air atsupply pressure' is `charged into the brake system of` the train. 'Thebrakes of the train are thus released and the inspector moves forwardfrom the remote l end of the train and completes his inspectionf Turningto Fig. V,;still anotherembodiment of the invention is shown, but itwillA beunderstcod that the general procedure of ymaking a brake test isno different with the structure of Fig. V than withv the structures oiFigs. I to IV; In F'gV the coupling fic serves to connect the apparatusto the line leading Ato the supply of compressed air, and coupling 3c(fragmentarily illustrated) serves to make connection tothetline leadingto the plunger assembly manually operated valve 2c) forms one branch,and pipe 50 (controlled by a'slide-valve 9c) provides the other.. And,as in the structures described, a gauge Ic and a manually operatedrelief cock 22o are arranged on the train-pipe side of the valve 2c.

The slide valve llc is by a rod 9d connected to a. plunger rod 55e; theplunger rod I5c carries two pistons-a piston I8c of relatively smalldiameter in a cylinder IGC, and a piston Id of relatively large diameterin a cylinder 16d. Between cylinderslc and Iid, a tubular housing I6eincloses the plunger rod IEC; rwithin housing IBea ring 30 is arranged;the plunger rod extends with sliding fit through this ring, and betweenthe ring and the piston Idd a helical compression spring 2Ilc isorganized, as shown. The ring 39 carries on each of its twodiametrically opposite sides a pin 3l, and each pin 3l extends radiallyoutward through a slot 32- A sec-y formed in the side wall of housing I6e. ond ring, a ring 33, is by a screw 34 secured externally upon thehousing IIe, and the righthand edge of this ring 33 provides an abutmentagainst which the projecting ends of the pins 3l bear. secured againstaxial displacement in right-toleft direction,A and the compressedkspring 20c, held captive between the ring 3G and the plunger I8d, tendsto move the plunger assembly I5c,

I8c, IIld to the right and shift the slide-valvev 9c into open position.The position of the internal ring 3l] may be adjusted axially of theplunger assembly, to regulate the magnitude of spring pressure on thepiston iSd, and such adjustment is effected by varying the otherwise xedposition of the external ring 33 axially of the housing Iie. Y When theapparatus is in service, the piston Ic is, manifestly, subject on itsleft-hand face to air at supply pressure, and piston ld is subject onits right-hand face to air at train-pipe pressure. When the brakes areset in applied positions, both the manually operated valve 2c and theslide-valve 9c are closed, and the pressure of the air on the left faceof piston Ille and the thrust of spring 20c of the left face of pistonltd are opposed and equalized by the pressure of air on theright-handface of piston I8d. When the inspector has checked over the appliedbrakes. and momentarily vents the trainpipe at the remote end of thetrain, the pressure of air on the right-hand side of plunger 18d drops;the equilibrium of the iorces acting on I5c, Ic, Id is destroyed, andthe plunger assembly shifts in leftto-right direction, sliding the valve@c into open position, withthe consequence that air flows from thesupply, through pipes 5b and 5I, into the train-pipe. Thus, thetrain-pipe is recharged and th-e brakes shifted into release positionswhile the inspector is at the remote end of the train. From this pointon, the test is completed in the usual-way. v

It will be perceived that in each of the structures described means areprovided for shifting from closed to open position a valve (9, 9a or 9c)in one of two lines of iiow. Inthe structure of Fig. I suchvmeansconsist in the spring I9, in that of Fig. III in the spring Illa, and inthat of FigV in the spring 20c and the piston ISC which is subject toair at supply pressure. in each of the structures, I provide meanssubject to train-pipe pressure for holding the valve, against theAurging `of such shifting means, in

Thus, the ring 30 within the housing is And` closed position. In thestructures of Figs. I to IV, the valve-holding means consist inatrip-arm I3 or Ita, together with a plunger l5 or I5a, subject tospring pressure in one direction of movement and train-pipe pressure inthe opposite direction, for throwing the trip-arm into release positionwhen the train-pipe pressure is reduced below a critical value. And inthe structure of Fig. V the means for holding the valve 9c in closedposition consists simply in the piston Id which, subject to thetrain-pipe pressure on its right-hand face, masters the forces tendingto shift the Valve into open position, until the train-pipe pressure isreduced below the` critical value.

When the valves 9 and 9a of the structures of Figs. I to IV are releasedand shiftedinto open position, they stand in open position, regardlessof train-pipe pressure, until they are manually reclosed. When the valve9c of Fig. V is opened and recharging of the train-pipe begins, the risfing pressure on the right-hand side of the piston iSd tends immediatelyto reclose the valve 9c. To the end that the valve, once opened, shallremain open until it is manually reclosed, I provide a spring-backedlatch that bears upon the plunger rod I5c; oneA or more notches 36V areformed in the plunger rod, and when in service the plunger assemblytravels to the right and opens the valve 9c, notches 36 come to aposition beneath the latch. The inner tip of the latch enters one of thenotches and locks the parts against return movement, with the Valve 9cin open position. When desired the latch may be manually withdrawn, andthe valve 9c returned to closed position. In order to prevent undueviolence in the operation of the plunger, an orifice-plate 5d isarranged in the line of flow between cylinder 56d and the air supply.

I claim as my invention:

1. In air-brake testing apparatus including a supply of compressedair,`an air line adapted to establish communication from said supply tothe train-pipe of a line of coupled cars whose brakes are to beinspected and tested, and a valve arranged in said air line; the hereindescribed refinements in such apparatus which include Valve-controllingmechanism including means for sluiting said valve from closed to openposition, means for securing said valve in closed position when airpressure in said train-pipe is above a critical value, and means adaptedupon reductionof train-pipe pressure to a point below critical value torender said valve-securing means ineffective, whereby an attendant atthe end of said line of cars remote from said apparatus may momentarilyvent said train-pipe and effect th-e immediate opening of said valve andthe recharging of the train-pipe to a pressure vabove said criticalValue.

2. The structure of', claim 1, in which said valve-shifting meanscomprise a spring tending to shift said valve from closed to openposition,

land a spring exerting tension on said piston in opposition totrain-pipe pressure.

3. In air-brake testing apparatus including a supply of compressed air,an air line adapted to establish communication from said supply to thetrain-pipe of aline of coupled carswhose brakes are to be inspected andtested, a valve arranged in said air line, and means for shifting saidvalve from closed. position to open position; theherein describedrefinements in such apparatus which include a device that, subject totrain-pipe pressure', is adapted to retain said valve in closed positionwhen train-pipe pressure is above a critical value, and means adapted,upon the reductionof train-,pipe pressure to a point below criticalvalue, to shift said device into valve-releasing position, with theeffect: that the valve, responding to the', valve-shifting meansmentioned above, is moved into open position, whereby an `attendantl atthe end of the line of cars remote from vsaid apparatus may momentarilyVent said train-pipe and eiect the immediate opening of said valve andthe recharging of the train-pipe to a pressure `above critical value. Y

4. In air-brake testing apparatus including a supply offco-mpressed air,an air line including two branches adapted to establish communicationfrom saidsupplyto the 'train-pipe of a line of .coupled cars Whosebrakes arey to be inspected l and tested, a manually operated valve inone of said branches, a valve in the other of said branches, and meansfor shifting saidflast valve value.

from' a position in which communication between air supply andtrain-pipe is interrupted to a position in which such communication isestablished; the herein described `renements in such apparatus whichinclude a device that, subject `to train-pipe pressure, is adapted toretain said valve-releasingposition, with the effect that the lastvalve, responding to the Valve-shifting `means mentioned above, movesinto open position, whereby an attendant at the end of the line of carsremote `from said apparatus may momentarily vent said train-pipe andeiect the immediate opening of said valve and the recharg-` ing of thetrain-pipe to a pressure abovecritical 5. 'I'he `structure of claim -4,in which said device-shifting member consists in a piston subject totrain-pipe pressure on one side, and a spring exerting tension on saidpiston in opposition to train-pipe pressure.

ROBERT SIMPSON. Y

